Every Thursday at 5 p.m. is “Thursday Tap,” at Jimmy’s No. 43, one of New York City’s top beer bars. That’s when host Jimmy Carbone taps a special keg/cask beer, usually a rare cask, a new beer or a hard-to-find small batch brew.

I happily happened to be the city recently on other business and made a point to stop in at Jimmy’s to try its unusual offering on that day, Zymatore Thornbridge Raven Black IPA, imported by B United International, a well-regarded importer that is working hard to challenge beer imbibers.

This was a black IPA developed for the U.S. market by Thornbridge Brewery in Derbyshire, England using five malt varieties and six different hops. It was then shipped to B. United’s facilities in Connecticut in temperature- and climate-controlled bulk liquid tankers for kegging, Jon Lundbom, the importer’s New York area manager told me in an email. A portion of the 3,500 liters imported went into wooden barrels for maturation. The barrels used for this brew previously held Ransom Winery pinot noir for three seasons before being filled with Ransom Distillery Whisky. Each barrel produces up to a dozen 20-liter kegs. Only two kegs made it to New York and the entire production, Lundbom noted, has sold out.

Thornbridge beers were first brewed in early 2005 after the establishment of a 10-barrel brewery in the grounds of Thornbridge Hall in Derbyshire. Initially the brewery focused on traditional cask beers modernized through the use of a wide range of hops, malts and other innovations. It soon began sweeping up national and international awards, which now number more than 200. A second brewery was opened nearby at Bakewell in 2009.

The Zymatore version of the Raven is an incredibly complex brew. Served in a Chimay chalice at Jimmy’s No. 43 for $12, it has a deep, black body with a thin beige head that fades rather quickly. The aroma is super sweet with notes of whiskey, wood, dark fruit and chocolate. It’s a beer to sip slowly. In the mouth it seems a tad thin but the flavors are intense: dark sweet chocolate with only the barest hints of resin but also oak, bourbon, and a hint of sweet wine. It tastes absolutely nothing like a black IPA, as virtually all the bitterness or hop character has been displaced by its barrel conditioning.

Now, I’m anxious to try other brews in the Zymatore range. For now, though, the Raven remains, alas, a sweet memory.